23 ms·

Ask HN: Can you recommend an “instant-switch” Monitor? Does one exist?

• sposeray 4y ago
  [dead]
• whalesalad 4y ago
  An external KVM switch might help but a lot of monitors suffer from this issue u fortunately and I don’t think anyone has benchmarked this
  • Matthias247 4y ago
    I'm using a pretty low level Displayport switch, and I think it also takes 4s to get a picture back. I guess the reason for this is actually the monitor and GPU. They will resync to each other after figuring out the peer capabilities and probably take some time for an actual frequency sync. Therefore I don't think any kind of switch would make it better - the switch would need to be intelligent enough not to drop the display stream but be an actual GPU on its own. Plus in this case it would need to have the exact same display signal frequencies that the attached GPUs use.
• brysonreece 4y ago
  Unrelated: OP, how do you like the U2723QE? Been trying to decide on pulling the trigger on two of them recently.
  • mrweasel 4y ago
    I have one, it's a really nice monitor, sadly there is a small "but". Sometimes, it starts flickering. I'm not completely sure what causes it, but closing the nearest Eletron app will normally fix it. Yesterday my kid wanted to see a video of volcanos on YouTube, followed a really bright picture of My Little Ponys, the monitor managed to start flickering and retain a shadow image of the little ponies, even as I switched between laptops and power cycled the monitor. This only happens on USB-C input, but seeing as the monitor have an Ethernet adaptor and works as a USB hub, USB-C is pretty much the reason I got it. Notes: It happens really rarely, and exclusively with the M1 MacBook Air. It might be a firmware update away from being fixed. Also Dells has an excellent return policy.
  • jemmyw 4y ago
    I've got a U3223QE which is the same just larger. The screen itself looks really nice, its bright, no complaints there. The stand is pretty good, reasonably tidy. My only complaint is that when it said USB-C hub I expected it to have USB-C ports for peripherals and it doesn't, only USB-A ports. My older LG has USB-C ports, so I know its possible. It's annoying because as more and more stuff switches to USB-C the only place to plug those in is the laptop itself, which means messing around with too many cables.
    • Handprint4469 4y ago
      Just in case you missed it, the U3223QE does have one USB-C port for peripherals. See [0], bottom right of the image. [0] https://i.dell.com/is/image/DellContent/content/dam/ss2/product-images/dell-client-products/peripherals/monitors/u-series/u3223qe/media-gallery/monitor-u3223qe-gallery-5.psd https://i.dell.com/is/image/DellContent/content/dam/ss2/prod...
      • jemmyw 4y ago
        That's the USB-C upstream port for if you connect PC-2 via HDMI and PC-1 is connected to the USB-C display port.
        • Handprint4469 4y ago
          I meant further to the bottom-right. Here: https://imgur.com/00KDqpq https://imgur.com/00KDqpq
          • jemmyw 4y ago
            thanks! I had no idea that one was even there. That sorts out my headphones!
  • adrian_b 4y ago
    I have its older version U2720Q and I am quite content with it, in a multi-monitor setup under Linux, using 30 bit per pixel, and also including a Dell loudspeaker system connected to U2720Q, used for audio via DisplayPort or HDMI. I assume that the upgraded version U2723QE should be only better, with the possible exception of firmware bugs like what was mentioned by the other poster.
• jtwaleson 4y ago
  Ugh yes, this should be benchmarked! I’m currently on a 34” widescreen Philips monitor and it takes about 10 seconds to switch, it annoys me majorly every time I do it. Just starting the overlay UI seems to take 5 seconds.
• blacklite 4y ago
  There are hardware limitations that make what you're asking for impossible. Use software solutions if you actually need instant switch. But you probably don't.
  • _rs 4y ago
    What are the hardware limitations? Surely this is possible if there was investment and interest in making this work? Or do the protocols really not allow this?
    • chmod775 4y ago
      In theory you could have a monitor that handles both signals all the time, buffering the output. Then it could switch immediately. It would however be more expensive, since you would need to duplicate at least some of the electronics within the monitor, a few of which also incur licensing/certification/patent/whatever fees.
      • yjftsjthsd-h 4y ago
        Why would you buffer? Monitors are capable of playing full-screen video, which implies the ability to update every pixel once per... 30hz? frame, doesn't it?
        • chmod775 4y ago
          Because when you want instant switching you need to already have the data you want to display available the moment someone flips the switch. You can't just tell the computer that you're now interested in the display data of the other display - that would incur latency. You'll have to be receiving the information for the second display the entire time, storing it in what is commonly called a framebuffer, aka a bitmap in memory somewhere. Most types of display have such a thing backing them anyways - one way or another - since they need to remember what they're supposed to display.
          • 4y ago
• stevebmark 4y ago
  No, nothing like that exists, and no KVM exists that does instant switching.
• Moru 4y ago
  This has been annoying me since I first tried a PC after using Atari computers since they were a thing. No matter what monitor I use, it will take for ever to switch input port or just a simple change of resolution. I was used to be able to switch resolution several times per frame, you could make a game with low resolution and color on the upper 3/4 of the screen and have the stats in higher resolution 4 color mode on the lower 1/4 of the screen without any sort of delay in the signal, you just set an interrupt on every scanline and if the monitor was painting the 300'th scanline, you witch mode and suddenly it's doing double resolution for the rest of the frame. Then switch back on the Vertical Blanc Interrupt at the start of the frame paint. I was quite surprised when the brand new PC needed 2-3 seconds just to switch resolution. And we are still there after 30-odd years? A KVM switch with analog signal was just the same, still long time to switch between signals. I'm using a remote control software to the local computers so I don't have to wait between every switch. With the added bonus that I can copy/paste between the computers without having to think.
  • bitwize 4y ago
    One of the reasons why you could switch modes mid-frame is because the concept of a "video mode" is fundamentally different on a PC than on an Atari or Amiga. On a PC, ever since the EGA, the adapter can output at different horizontal and vertical scan rates and the monitor can adapt to the requested mode from the video card. That's why switching video modes takes a couple seconds and may involve a "click" or two. Upon mode switch, the monitor must resync to the new signal. On the Atari and Amiga, the horizontal/vertical scan rates are constant; the only thing that changes is how scanout turns pixels in video memory into signals for the CRT.
    • M95D 4y ago
      No. I have a Sony G520 CRT monitor with a hardware switch. When I flip the switch, the other image appears in less than a second. In the past I had a Samsung (I don't remember the model) that made the switch without even interrupting the electron beam, in mid-frame. First 2 frames were garbage, until it sync'd to the new signal, but it only took a blink of an eye to switch (at 85 Hz). It was also very quick to sync after a mode change. I could see BIOS screens that modern flat displays are to slow to display before they dissapear.
• alin23 4y ago
  My old LG 27UD88 switches in about 1 second when pressing the relevant hotkey in Lunar (https://lunar.fyi/ https://lunar.fyi/) It’s not instant but input switching through DDC is the fastest possible method. That’s because the input that will be switched to is already connected and receiving video in the background, skipping the HDMI/DP protocol handshake and going straight into rendering the new video on the screen.
  • chid 4y ago
    yeah I think also that with macbook the display is constantly sending video to the display (as there is no way to disable extenral displays).
• hunter2_ 4y ago
  If you can get HDMI from all your sources, something like this might work for 1080p: https://www.bhphotovideo.com/c/product/1507214-REG/blackmagic_design_swatemmini_atem_mini_switcher_control.html https://www.bhphotovideo.com/c/product/1507214-REG/blackmagi... More options, like if you need higher res: https://www.bhphotovideo.com/c/buy/Live-Switcher/ci/2865 https://www.bhphotovideo.com/c/buy/Live-Switcher/ci/2865
• chmod775 4y ago
  You'll need a fancy KVM switch that does more than merely acting much like a physical switch would. Something like this should probably work: https://www.rextron.com/product-4K-2-Port-Full-Frame-PBP-KVM-Switch-with-Roaming-Mouse,-4K-Scaler---PIP-PBP-Function-MBKG-312.html https://www.rextron.com/product-4K-2-Port-Full-Frame-PBP-KVM... Edit: The one above is merely the first one I found, not a recommendation. Be aware that such things may incur extra latency, since it's not just passing signals through, but rather processing them and repackaging them.
  • siva7 4y ago
    There is no price listed for this switch. How much does it cost?
    • upon_drumhead 4y ago
      I have a few tesmart HDMI switchers are they are fairly reasonably priced (~$100) and switch decently fast (Under 1 second usually). Occasionally I have to switch the unit off/on if it gets confused, once a quarter or so. There's a switch on the front of the unit so it's not terrible. They also support hot key switching, so my hands don't need to leave the keyboard to switch, which is nice.
      • Aeolun 4y ago
        > They also support hot key switching, so my hands don't need to leave the keyboard to switch, which is nice. Note that the keyboard interception is less than stellar, so it’s equally possible your keyboard just won’t work correctly when plugged into their magic port. My copy-paste is impossible when plugged in (well, dropped 2 out of 5 times, which might as well be).
  • IshKebab 4y ago
    Unfortunately I have a similar KVM switch and it is very much not instant. In the same 4 second ballpark as OP. Annoys me too but I just put up with it since I don't have to switch very often and it's sure faster than switching inputs on my monitor's shitty OSD which is what I used to do.
• GianFabien 4y ago
  I suspect there is a tiny CPU inside the monitor that looks at a variety of things before deciding how to decode the signal and present it. As @alin23 notes, DDC protocol is also handled. Obviously the manufacturers are using the lowest cost BOM that they can get away with and that would probably mean a $1 microprocessor in charge of the "smarts".
  • fsh 4y ago
    Even a $1 micro should be able to handle a few bits of resolution information in less than a millisecond. This can't be it.
    • thefz 4y ago
      There's a lot going through between your OS and the monitor when you plug a display, really. HDMI and DP are two-way protocols. Expecting everything instant-on is naif.
      • fsh 4y ago
        Then there must be something badly wrong with the protocol and/or implementations. Negotiating a few bits over a high-quality cable link should be instantaneous.
        • plasticeagle 4y ago
          There could be, but there are (at least) three parties involved in whatever's causing the slow monitor response. I find it irritating even without a switch, just plugging in my external monitor should not take what seems like thirty seconds to actually turn on. But in reality, you've got whatever tiny micro is inside the monitor, talking to whatever's on the graphics card, in turn talking to display drivers and who-knows-what-else on the PC side. Slightly related to this, in some ways, is things like wifi connection. I have an ESP8226 that I've built a clock around. That thing will connect to the wifi, negotiate security, contact a time server, probably within one second. None of that is down to my ingenuity, it's literally how it works out of the box. So the problem may just as much be on the OS side, rather than the monitor and the E-DID protocol.
• trap_goes_hot 4y ago
  If I were you I'd use a hardware KVM device that goes to a single input source on the monitor and keep the monitor always-on with a black screen saver to prevent burn-in. I was in a similar situation when I wanted a easy way to switch between speakers/headphone at any time without messing with settings or apps. I ended up using a physical switch. https://www.amazon.com/gp/product/B008BMLXAU/ https://www.amazon.com/gp/product/B008BMLXAU/
• deleted 4y ago
  [deleted]
• lofaszvanitt 4y ago
  There are multiple input (5xHDMI) same output (1x HDMI) switches on the net, which feeds one input of the monitor and you can change the source on the adapter with a round robin button. It's almost instant. Another cool feature is whenever a new input source is detected it automatically feeds that to your monitor. I haven't seen the configuration you need, but if you can use adapters to convert each source to HDMI, it works like a charm. It's called an HDMI switch.
  • nicexe 4y ago
    switching between 2 inputs would take between 1x and 4x (x being the time to switch to the next input) depending if it is from A to B or B to A.
    • goosedragons 4y ago
      Even the cheap HDMI switches all come with a remote so you can jump from input 2 back to 1.
• apelapan 4y ago
  Slow screens, they annoy me so much too! Somewhat on this topic, I wish one could compare motherboards by the time-to-boot delay. If reviewers start benchmarking something, manufacturers will optimize for it eventually.
• teekert 4y ago
  Yeah would be nice to be able to alt-tab between monitors (or I should say: sources). I never understood why it is so slow. I have a somewhat older Samsung TV and I even have to cycle all the inputs (8?) to arrive a the correct one and it takes 1-3 sec on every input before I can get to the next. Absolutely maddening. But I guess manufacturers were too busy making 3D a thing and then "curved". Maybe they can now decide to fix some basics?
• VinLucero 4y ago
  I wish this existed. Samsung Odyssey G7 has the same issue.
  • leaveyou 4y ago
    iiyama 34" is even worse.. 10-15 seconds delay before seeing the image. One of my worst buys ever.
• voxelghost 4y ago
  I don't know the specifics of your monitor. But you say the source is in power-save mode? I think then it has also signaled to the monitor to enter power-save mode. So if your monitor supports it, turn off energy-saving mode settings might fix the issue. It might also be less annoying to wait 4 seconds, if you think of it as helping to save the planet ;-)
• tcbyrd 4y ago
  Closest you’ll get is something like a Blackmagic ATEM switcher, using “Program” as the output. Then you can map a software key to swap it out in a single frame. As discussed in another thread, the computer has to be sending the display signal to some device that is seen as a display, and that switcher keeps the video from both PCs buffering at 60 or 30 fps. To the computer it can’t know the display switched and the display can’t handle two simultaneous streams, so you have a device in the middle that bridges that. Down side is depending on the quality of the switcher you might get 1-2 frames of lag because it’s optimizing for frame accurate sync to ensure the least possible “flicker” when the source is switched.
  • rsync 4y ago
    Tangent ... these BlackMagic 2.5" multidocks are so cool: https://www.blackmagicdesign.com/products/blackmagicmultidock https://www.blackmagicdesign.com/products/blackmagicmultidoc... I don't really have a use for one but I wish I did ...
• pontifier 4y ago
  This is one thing I really miss about analog tv. You could switch channels as fast as you could press the button. Everything now is so slow.
  • montag 4y ago
    Yes! I remember running my finger down the column of electrical contact switches and changing the channel at 60 fps. "brrrrrrip!"
  • dmurray 4y ago
    I assume this is for a different reason - buffering and stream compression, you have to wait for a key frame before your TV can display anything. Similar root cause though - technology becomes available that makes the steady state performance much better in return for some setup costs, the setup costs are worth paying in almost all applications so it's an obvious choice to go with the new technology but still annoying when you encounter its drawbacks.
    • brokenmachine 4y ago
      Good point. What would be nice is if it had a low-quality stream with more keyframes so it could switch quickly and then go to the higher quality stream when that gets to a keyframe. But I can see why that kind of complexity wouldn't be added just so you can switch quickly to 3 seconds of low quality video.
  • fps_doug 4y ago
    This is one of the things on my TODO-list for when I stumble upon a way to have infinite amounts of time: Learn "FPGA 'n stuff" and build my own display controller. Like many people here, I don't understand why this takes so much bloody time. Not just the input switching, but also switching resolution or refresh rate on the same input. So either I'd have an a-ha moment and see why it's not possible (more likely outcome), or well, it'll just work and I can write a cool hackaday post. The EDID explanation given in the comment currently at the top doesn't make too much sense: Even if the display is off and not in some super hardcore energy saving mode, EDID works, i.e. your computer can query the EDID data from the screen and know what its preferred resolution is, etc. Likewise, even if your display is switched to HDMI-1, a machine connected to HDMI-2 can already be outputting 1080p60 to it, so why does switching inputs take more than a few milliseconds? Afaik (and I only have very rough knowledge here), there is no side-channel in HDMI/DVI that tells the display what mode it's actually receiving, so the display has to look at the signal and make sense of it. So you have to put some brains in it. But that can hardly take several seconds, i.e. hundreds of frames? Maybe two or three frames! I could see this being a cost cutting measure, maybe doing the dumb implementation that takes seconds instead of milliseconds saves you a cent or two per device.
• atoav 4y ago
  HDMI Switching like that takes long because there is a EDID negotiation going on between the minitor and the input devices. If you want to switch fast and often your best bet is getting an HDMI switcher that is basically always connected to the monitor and both sources and then toggles between the two. Beware of the supported resolutions and framerates. A cheap hack would also be to connect your second source to the first using a HDMI Grabber (basically a HDMI-source-to-USB-webcam-converter) and open a fullscreen window displaying that. Then you could e.g. switch by switching virtual desktops. Another post recommended rhe Blackmagic Atem, this should also work.
  • Aeolun 4y ago
    Even with one of the fancy KVM switches that were recommended here my switching isn’t instant. It did go down from 10-20 seconds of flickering to +/- 2 seconds though. May not be worth it if you are already at 4s though.
    • Raglov 4y ago
      What model do you use that gave you 2 seconds switching time? One of the mentioned Rextron or something else?
      • causi 4y ago
        My "NEWCARE HDMI 2.0b Switch 3 in 1 Out" switcher is that fast.
        • mwidell 4y ago
          Thanks just ordered one!
        • patentatt 4y ago
          Can I inquire how you switch inputs (mouse, keyboard) along with the hdmi?
          • 4y ago
• kimburgess 4y ago
  Not on a monitor (that I'm aware of), but it is a major feature of signal distribution equipment for installed AV and broadcast. A large part of the delay that you are seeing is from EDID negotiation and HDCP. This happens of the 100kbit/s DDC channel and requires a bit of back and forth. On the above systems this is pre-negotiated so that switching can take place across a single frame. A lot of that equipment is likely price prohibitive for desktop use, but you may be able to reduce the time a little with sidestepping that process either in your machine setup or with an external bit of lower cost hardware like and EDID emulator (e.g. https://www.extron.com/product/edid101h4kplus https://www.extron.com/product/edid101h4kplus).
  • mort96 4y ago
    100kbit/second is still blazing fast for communication which ought to be on the order of a hundred bytes... 4 seconds at 100kbit/s is 50kB. Why does it have to be so chatty?
    • kimburgess 4y ago
      When the input is first selected here's will be a hot plug detect, EDID request and an EDID response. That response can be up to 32kB so anywhere up to ~2 seconds depending on how many extension blocks are in use by the display. Here's a nice breakdown on more of what happens there: https://research.nccgroup.com/wp-content/uploads/2020/07/hdmi_-_hacking_displays_made_interesting.pdf https://research.nccgroup.com/wp-content/uploads/2020/07/hdm.... When a suitable set of image parameters have been agreed HDCP (may) then step in to ruin your day. Again a nice walkthrough of that is available here: https://blog.cryptographyengineering.com/2012/08/27/reposted-cryptanalysis-of-hdcp-v2/ https://blog.cryptographyengineering.com/2012/08/27/reposted.... As other commenters have correctly noted, there's definite room for improvement. One thing to remember though is this involves hardware that can be in operation for the order of decades so there's a lot of cruft that accretes in order to maintain compatibility. Frankly it's mildly impressive that for the most part all the above happens in silence and continues to (mostly) work.
• modeless 4y ago
  I bought one of the first GSync monitors many years ago (ASUS PG278Q ROG Swift) and it goes from sleep to displaying an image in just a fraction of a second. It's totally amazing, way faster than any other monitor I've ever seen, including newer GSync monitors. It only has one single input port though. I've never tried hooking it to a KVM, but I bet it would switch super fast. Maybe try one of the first gen (2014) GSync monitors along with a DisplayPort KVM, if that can work for you. It's my understanding that the first gen GSync monitors all used the same monitor driver board that Nvidia made, so they probably behave similarly. Honestly I didn't know how much I needed fast wakeup until I had it. It's a way better feature than GSync, yet monitor and TV reviewers generally ignore it completely. There are probably newer monitors with fast wakeup but it's impossible to know without testing. My TV takes like 8 seconds to even turn on its backlight and it's just ridiculous.
  • glowingly 4y ago
    My native Gsync monitor, a now discontinued LG 32GK(?)650 is quite fast as well. I’ve complained a tiny amount about monitor reviewer blind spots, and this is one of them. The speed of every interaction on this monitor is very very fast. It is why I am very unwilling to let it go, even if it keeps me locked into the Nvidia side of things, since my monitor predates native Gsync modules that support DP Adaptive Sync and HDMI VRR.
• bitwize 4y ago
  OK, remember when modems were like EEEEEEEkRrRrRrRrRrRrRbaBONGbaBONG.... That was handshaking, and it was how modems figured out which speeds and protocols each other supported so they could figure out how fast to transfer data and how to encode it. Monitors are kind of the same. There's handshaking that goes on each time you connect a monitor to a video source. Like (and I'm totally making this up): - Hi, I'm an AMD video card. - Hi, I'm an LG monitor. - You're a monitor? Great! I have some data I'd like to display. What resolutions, refresh rates, and color depths do you support? - Well, I support 1920x1080x24bpp@60Hz, and 1600x900x24bpp@70Hz, and... - Cool! I'd like to display at 1920x1200x24bpp@60Hz, please. - Sure thing, hang about while I get that set up. [Monitor CPU sets up whatever framebuffers, scalers, etc. are necessary to display at 1920x1200x24bpp@60Hz] - Right then. Ready for your first frame. - All right, first frame incoming... Only then will you get your display. This can take a couple seconds.
  • netsharc 4y ago
    I have an Asus monitor, it has DVI, HDMI, VGA. The HDMI has a quirk, I forget what, so I use a HDMI to DVI cable to connect my laptop to it. And when I switch sources away from DVI, the laptop doesn't think the 2nd display disappeared. So I don't think there's a handshake being done when switching back, because they were holding hands the whole time. I think the quirk was, if I have something plugged into the VGA input, and the HDMI input goes to powersave mode, the monitor "helpfully" says, "Oh, no HDMI signal? Let me switch sources!"
  • neilalexander 4y ago
    > Monitors are kind of the same. There's handshaking that goes on each time you connect a monitor to a video source. If the connector is high bandwidth enough to send hundreds of thousands of pixels 60 times a second, how can it possibly be so slow to send a few bytes of handshake or EDID data? Handshakes should be happening nearly instantly. You can complete opening a TCP connection to the other side of the world in a fraction of the time it takes to switch input on the average monitor.
    • int0x2e 4y ago
• 3np 4y ago
  Tangentially related: I find many monitors that look great on paper are a real annoyance when it comes to controls, be it brightness/contrast or input switching, making those 4s irrelevant in comparison. Between recent models of Acer/Dell/Eizo/LG, I found Eizos to pose the least friction so far, with the LG (may be model-specific) a surprising worst. Reply to this comment with your anecdotes! EDIT: To address the OP: Switching from an offline source to an active one is def smoother than you describe on my Eizo FlexScan EV series - I estimate it to <2s. The input switching is bearable enough that using the PbyP (two input sources split) is something I occasionally do, whereas with Dells it was just annoying enough to make me not bother.
  • alanbernstein 4y ago
    My Samsung monitor has a 4-way joystick control for navigating the menu. It's the worst physical monitor menu UX I've used. It's also on the back of the monitor, which makes it a pain to reach. When I bought it, I only had one input, so it didn't bother me. Now that I have two inputs, and I switch a few times a day, I'm considering getting a new monitor, in some part to move to one with better input controls.
• jwr 4y ago
  I'm spending anywhere from 10 to 30 seconds every time I want to turn my monitor on. It's a game of fiddling with the buttons, trying to get it to wake up faster. As an added bonus, the built-in firmware is terrible, and presents a "quick-switch" list of inputs which is different from the "normal" list of inputs, because… well, I don't know, just to make customers miserable, I guess.
• EspadaV9 4y ago
  There are applications that seem to switch faster than using the OSD, like [0], however, they need an OS running to use. 0: https://codeberg.org/Okxa/qddcswitch https://codeberg.org/Okxa/qddcswitch
• spants 4y ago
  I was annoyed by this too. My solution was to buy a 49" samsung monitor and have either 50:50 or 1/3:2/3 split on the screen so I can see both at once. If I only want one active I can change the source but this has the flicker/delay as noted. I run Barrier software on both to move one keyboard and mouse between the screens.
  • texasbigdata 4y ago
    Can you link to the software? It’s a pretty common term but sounds interesting
    • fragmede 4y ago
      It's the same as Synergy which is at https://symless.com/synergy https://symless.com/synergy
      • mkl 4y ago
        Unlike Synergy, Barrier is entirely open source.
        • texasbigdata 4y ago
          I actually pay for Synergy hence the curiosity :) Thank you kind stranger.
  • sandos 4y ago
    Doesn't this split incur some horrible scaling artefacts? Does it work well even for text? I have a similar function on my LCD monitor and its basically useless, it seems it throws away 50% of the pixels or something.
• klntsky 4y ago
  > i.e. due power save mode This is your problem, isn't it? I never use power save mode and have no problems with these delays.
• gfd 4y ago
  Gigabyte gaming monitors come with a physical kvm button: https://www.gigabyte.com/Monitor/M32U https://www.gigabyte.com/Monitor/M32U
  • roldie 4y ago
    Thanks for sharing, I didn't know these even existed!
• adastra22 4y ago
  > The monitor is on a switched off source i.e. due power save mode Do you want your cake, or you do want to eat it too?
• prmoustache 4y ago
  You might be able to do that with a master computer running OBS in studio mode, an HDMI capture car for each source you want to connect, projecting the scene to your Monitor all the time and some hardware device with buttons to switch scene. But this is kind of a hack and you would possibly have undesired latency, especially noticeable when typing fast and moving the mouse.
• Terretta 4y ago
  Recently (last few months) I've been testing HD Fury VRRoom, and am happy with it, as it allows switching instantly regardless of monitor, by having negotiation already set up: https://hdfury.com/product/8k-vrroom-40gbps/ https://hdfury.com/product/8k-vrroom-40gbps/ It maintains a live connection to each of 4 x HDMI inputs, 2 x HDMI outputs (mirrored or matrixed), and 1 x eARC audio output, and can switch between them "instantly" as you ask. You can switch with a button at your desk, or via API. I selected this model because it supports (a) up to 8K and we use 5K monitors, both full 5K and ultrawide 5K, and (b) variable refresh rate (VRR) at 4K@120hz for gaming. In a teleconference room with e.g. a big on the wall and a small screen on the table showing same or different sources, this lets you have multiple input sources (e.g., teleconf system, laptop, game system, and OTT TV source) that 'just work' without users having to know how to make it work. The feature list for video includes: - Unlock true VRR/FRL on Samsung Q90/QN900/QN95 and similar models - Up to 8K60 444/RGB 12-bit via DSC at 96Gbps - World First 40Gbps Upscaler, Splitter, Switcher with full audio extraction for VRR and any signals - Play Xbox 1X games at 4K120 Dolby Vision on LG C9, BX & SONY HDMI 2.1 TV - Work from ANY HDMI source to ANY HDMI, ARC or eARC sound system - HDMI 2.1 Full Audio/Video passthrough up to FRL5: 40Gbps/1200MHz - Upscale FRL5 and ANY signals 2K>4K, 4K>8K and 2K>8K up to 120Hz (no upscale for VRR/1080i/720p/480i-p) - Downscale ANY FRL0/TMDS signals 8K>4K, 4K>2K or 8K>2K up to 120Hz (no downscale for FRL5/VRR tbd) - Add or remove any input from the CEC network at any time via webserver, APP, IR/IP or RS232 And for audio, it solves getting eARC signal to amps or soundbars that can support Atmos when the monitor or TV doesn't support it: - Full Audio from ANY HDMI source (including VRR signal) to ANY HDMI, ARC or eARC sound system - Full Audio up to Atmos/TrueHD from any HDMI source to SONOS Arc/Beam2 or any eARC sound system - Solve SONOS Arc/Beam2 + other lip sync issue when using external HDMI sources connected to eARC TV If you get one and find yourself needing support, join their Discord server.
  • js2 4y ago
    HD Fury is also well known among home theater enthusiasts and they make some really amazing devices. They’ll also add new features based on fairly niche demand. For example they allow LLDV to be used with projectors that don’t natively support it (JVC, Epson) including sending serial commands to the projector to change its video mode when HD Fury device detects an HDR signal. Anyway, pretty amazing if niche devices with fantastic customer support and willingness to add functionally for relatively small numbers of users.
• foresto 4y ago
  This delay also often happens when I switch between linux virtual consoles (Control+Alt+F7/F8), despite both of them using exactly the same X display settings. Not always, though. The switch sometimes happens instantly. (At least, it has been this way since I replaced my Nvidia card with an AMD. I don't recall whether the Nvidia ever switched instantly.) I wish I knew what conditions make it instant, so I could try to make it happen consistently.
• jenscow 4y ago
  Maybe solving your problem in other ways: 0: I use `ddcutil` (on Linux), it takes about 2 seconds for the switch: `ddcutil -b $bus setvcp 0x60 $source` 1: Use something like NoMachine or VLC - would probably cause more problems if you've got devices that go into power-save mode 2: Ensuring that your devices are outputting the exact same mode may decrease the time.
  • alanbernstein 4y ago
    Would you mind sharing what monitor you have? Mine "supports" DDC, but switching inputs from CLI doesn't work.
• sandworm101 4y ago
  Your answer wont be found in monitors. You need a media switch, a good one like thise used in the enteraimment industry for broadcast-quality transitions between inputs. Alternatively, look into streamer-quality "media switches" used by streamers with multiple camera rigs. https://restream.io/blog/best-video-switchers/ https://restream.io/blog/best-video-switchers/
• evadne 4y ago
  You need a video matrix such as: https://www.lindy.co.uk/audio-video-c2/matrix-switches-splitters-c166/4x2-hdmi-4k60-matrix-p12068 https://www.lindy.co.uk/audio-video-c2/matrix-switches-split...
• lcedp 4y ago
  I think HDMI EDID Emulator can be useful. For instance, https://smile.amazon.co.uk/gp/product/B095JXDM84/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 https://smile.amazon.co.uk/gp/product/B095JXDM84/ref=ppx_yo_... In my (very poor) understanding, it 'caches' the information about monitor capabilities. I used it to prevent my laptop from rearranging windows when my monitor goes to energy saving mode.
• Temporary_31337 4y ago
  Maybe get a dedicated display for your devices or just get a huge 4K or 5k display with PIP mode or vnc/remote into the machines so that the switch is software based.
• c7b 4y ago
  I like using KVM switches for connecting multiple sources - if you are using multiple laptops/PCs, it has the benefit that you can use the same keyboard/mouse for all of them.
• mschuster91 4y ago
  If you got the cash, get a Blackmagic Atem Mini video mixer and an appropriate amount of x-to-HDMI dongles.
  • rollcat 4y ago
    I have a hand-me-down Atem Mini that "survived" many, many productions, and honestly I wouldn't recommend it - the internal fan noise is getting worse, and I wouldn't want it next to my setup. I haven't tried it with a computer but I think mouse-to-screen latency would be a limiting factor.
• alanbernstein 4y ago
  I appreciate this question, I would also appreciate a solution, and the explanation of why it happens is interesting. However, what I really want is just to be able to switch the input via command line. I know that there is a protocol that supposedly allows this (ddc?), But it seems that support for it is not standardized. This means the feature I want can't be found in the product specs. So my question: what's a monitor I can buy that will allow me to switch inputs by command line? (Ideally 4k)
  • balefrost 4y ago
    If you just need "switch using keyboard", not necessarily "switch using shell", some KVM switches allow input switching using keypresses. For mine, it's <SROLLLOCK> <SCROLLOCK> <1-4> <ENTER>, though I think that can be customized.
    • alanbernstein 4y ago
      Well, what I actually want to do is switch via my DIY macropad. My keyboard switch goes through that, without relying on any of the main computers. I had a cheap HDMI switch that worked the same way, but it just stopped working reliably after a month. I sometimes want independent control of the keyboard switch and the monitor switch, so I'm not sure if a KVM is the best option for me.
  • Davertron 4y ago
    I think Dell has pretty good support for this, I had a pretty old Dell model before my current monitor and ddc worked fine with it. I now have an AORUS FO48U and it also supports it. I'm not sure it's always listed as a feature though when you're buying a monitor so it might be tricky. FYI, I originally learned about this stuff via https://haim.dev/posts/2020-07-28-dual-monitor-kvm/ https://haim.dev/posts/2020-07-28-dual-monitor-kvm/.
  • alin23 4y ago
    In 5 years of getting support emails for Lunar (https://lunar.fyi/ https://lunar.fyi/), LG monitors were the least mentioned of all. They seem to have the best DDC compatibility of all monitors. I also keep a public monitor database here where you can check if a specific monitor usually works with DDC or not: https://db.lunar.fyi/ https://db.lunar.fyi/ The problem with LG is that they report very generic names so they can't be filtered well in the database. You can see what I mean with this query: SELECT DISTINCT ON ("DisplayProductID") name, ddc, "resolutionString", "refreshString", "dotsPerInch", "isHiDPI", "isRetina", "DisplayProductID" FROM displays WHERE ddc AND "is4K" AND width IS NOT NULL AND NOT "kCGDisplayIsVirtualDevice" AND NOT "isAirPlayDisplay" AND NOT "isTV" AND "DisplayProductID" != 0 AND name NOT LIKE 'Unknown Display%' -- Filter out those in a semi-connected state AND name LIKE 'LG%' AND "DisplayProductName" LIKE 'LG%' ORDER BY "DisplayProductID" DESC LIMIT 10; Also keep in mind that the GPU used and the hub/dock/adapter can affect this, so aim for as few indirections as possible. A direct connection is almost always the best.
• whywhywhywhy 4y ago
  100% convinced we wouldn’t live in a world with trash like this if just a few more people would say “it’s very slow, can you make it faster? No I don’t care what the excuse for it being slow is I still think it can be faster, currently it feels cheap and awful” Weird how you say that then the thing that was “that’s just the way it is” is often completely solved in the next day or two.
  • patentatt 4y ago
    Having been on both sides of that very dynamic, I'm inclined to agree.
  • bob1029 4y ago
    > if just a few more people would This is the challenge... Not many are willing to question why things are the way they are anymore. In fact, this seems to be frowned upon in more circles than ever before. "don't rock the boat", "it is what it is", et. al. The only way out of this hell is to begin construction of your own ladder.
• dizhn 4y ago
  I am using the setup from this blog as a software kvm solution and would love for it to be faster but it is manageable with my HP monitor. Link: https://xpufx.com/posts/hundred-percent-software-kvm-switch/ https://xpufx.com/posts/hundred-percent-software-kvm-switch/
• magixx 4y ago
  If you're looking for a monitor with responsive software avoid the Gigabyte M28U like the plague. Sure it's got 4k 144hz and when that works it's visually great. However, monitor sleep/wake or any other funcitonaly such as switching inputs had been a nightmare to the point that the most effective way to switch inputs quickly is to turn it off and on. At this point I'm really considering selling it for something with better software.
• brokenmachine 4y ago
  I have an OLED monitor and between being completely black with no input, and taking a long time to switch inputs, I'm often not sure if it's actually turned on or not.
• leriksen 4y ago
  I have a Samsung S34J55x, and a DisplayPort 4 port KVM from Lindy. I have 3 laptops connected, all different makes (lenovo, dell, ms), and they generally take 1-2 sec to switch between machines. Maybe the key is the video interface eg HDMI vs DVI vs DP, be an interesting experiment.
• yourapostasy 4y ago
  Take a look at ConnectPro video emulators [1]. Mentioned [2] and praised [3] here on HN before, but there are limits on their KVM's [4] to watch out for so just a caution to don't hastily ascribe the same performance from their emulators to their KVM's if you're also messing around with switching configurations. [1] https://connectpro.com/collections/video-emulators https://connectpro.com/collections/video-emulators [2] https://news.ycombinator.com/item?id=24362388 https://news.ycombinator.com/item?id=24362388 [3] https://news.ycombinator.com/item?id=24362975 https://news.ycombinator.com/item?id=24362975 [4] https://news.ycombinator.com/item?id=26906688 https://news.ycombinator.com/item?id=26906688
• cheri9 4y ago
  [dead]